如果想对一个文本文件一行行的读，然后在对每行数据处理 用JAVA的IO流里的哪个类效率最高啊

[大地之子]

如果想对一个文本文件一行行的读，然后在对每行数据处理 用JAVA的IO流里的哪个类效率最高啊

[小灯光环]

读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

[大地之子]

引用 1 楼 wlwlwlwl015 的回复:

读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

要包装吗 我看网上人家读文件都是一层包着一层的流 不知道一行一行读文件用哪个IO的文件流最快啊 好多网上都是一层包一层啊 你是怎么写的呢

[小灯光环]

引用 2 楼 u014039623 的回复:

[quote=引用 1 楼 wlwlwlwl015 的回复:] 读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

要包装吗 我看网上人家读文件都是一层包着一层的流 不知道一行一行读文件用哪个IO的文件流最快啊 好多网上都是一层包一层啊 你是怎么写的呢[/quote] Java的IO流的设计就是装饰模式，你看到的一层一层就是这样。比如：

BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("csdn.txt")));

而且BufferedReader本身设计的就是通过缓冲方式读取文本，减少了很多io操作，效率还是相当高的。

[大地之子]

引用 3 楼 wlwlwlwl015 的回复:

[quote=引用 2 楼 u014039623 的回复:] [quote=引用 1 楼 wlwlwlwl015 的回复:] 读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

要包装吗 我看网上人家读文件都是一层包着一层的流 不知道一行一行读文件用哪个IO的文件流最快啊 好多网上都是一层包一层啊 你是怎么写的呢[/quote] Java的IO流的设计就是装饰模式，你看到的一层一层就是这样。比如：

BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("csdn.txt")));

而且BufferedReader本身设计的就是通过缓冲方式读取文本，减少了很多io操作，效率还是相当高的。[/quote]好的 3QS 是不是直接就BufferedReader br = new BufferedReader("csdn.txt"); 然后就可以一行一行的读了啊

[小灯光环]

引用 5 楼 u014039623 的回复:

[quote=引用 3 楼 wlwlwlwl015 的回复:] [quote=引用 2 楼 u014039623 的回复:] [quote=引用 1 楼 wlwlwlwl015 的回复:] 读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

要包装吗 我看网上人家读文件都是一层包着一层的流 不知道一行一行读文件用哪个IO的文件流最快啊 好多网上都是一层包一层啊 你是怎么写的呢[/quote] Java的IO流的设计就是装饰模式，你看到的一层一层就是这样。比如：

BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("csdn.txt")));

而且BufferedReader本身设计的就是通过缓冲方式读取文本，减少了很多io操作，效率还是相当高的。[/quote]好的 3QS 是不是直接就BufferedReader br = new BufferedReader("csdn.txt"); 然后就可以一行一行的读了啊[/quote] 不行啊，bufferedreader的构造函数必须要传一个read对象： Constructor and Description BufferedReader(Reader in) Creates a buffering character-input stream that uses a default-sized input buffer. 你直接读本地文件用我上面写的就可以。

[大地之子]

引用 6 楼 wlwlwlwl015 的回复:

[quote=引用 5 楼 u014039623 的回复:] [quote=引用 3 楼 wlwlwlwl015 的回复:] [quote=引用 2 楼 u014039623 的回复:] [quote=引用 1 楼 wlwlwlwl015 的回复:] 读一行的话就用BufferedReader，它有个readLine()方法，就是返回一行的数据，参考一下官方文档： public String readLine() throws IOException Reads a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed. Returns: A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached Throws: IOException - If an I/O error occurs See Also: Files.readAllLines(java.nio.file.Path, java.nio.charset.Charset)

要包装吗 我看网上人家读文件都是一层包着一层的流 不知道一行一行读文件用哪个IO的文件流最快啊 好多网上都是一层包一层啊 你是怎么写的呢[/quote] Java的IO流的设计就是装饰模式，你看到的一层一层就是这样。比如：

BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("csdn.txt")));

而且BufferedReader本身设计的就是通过缓冲方式读取文本，减少了很多io操作，效率还是相当高的。[/quote]好的 3QS 是不是直接就BufferedReader br = new BufferedReader("csdn.txt"); 然后就可以一行一行的读了啊[/quote] 不行啊，bufferedreader的构造函数必须要传一个read对象： Constructor and Description BufferedReader(Reader in) Creates a buffering character-input stream that uses a default-sized input buffer. 你直接读本地文件用我上面写的就可以。[/quote]灰常感谢啊